2
2-8
Ver.0.10
CPU
2.6 Data Formats
2.6.2 Data Formats
(1) Data formats in register
Data sizes in M32R registers are always words (32 bits).
When loading byte (8-bit) or halfword (16-bit) data from memory into a register, the data is sign-
extended (LDB, LDH instructions) or zero-extended (LDUB, LDUH instructions) into word (32-bit)
data before being stored in the register. When storing data from M32R register into memory, the
register data is stored in memory in different sizes depending on the instructions used. The ST
instruction stores the entire 32-bit data of the register, the STH instruction stores the least
significant 16-bit data, and the STB instruction stores the least significant 8-bit data.
Figure 2.6.2 Data Formats in Register
Rn
0(MSB)
31(LSB)
<When loading>
Byte
Rn
0(MSB)
31(LSB)
Halfword
Rn
0(MSB)
31(LSB)
Word
Sign-extended (LDB instruction) or
zero-extended (LDUB instruction)
From memory (LDB,
LDUB instructions)
<When storing>
Rn
0(MSB)
31(LSB)
Byte
Rn
0(MSB)
31(LSB)
Halfword
Rn
0(MSB)
31(LSB)
Word
To memory (STB instruction)
To memory (STH instruction)
To memory (ST instruction)
From memory (LDH, LDUH instructions)
From memory (LD instructions)
Sign-extended (LDH instruction) or
zero-extended (LDUH instruction)
24
16
24
16
Summary of Contents for M32170F3VFP
Page 42: ...1 1 24 Ver 0 10 OVERVIEW 1 4 Pin Layout This is a blank page ...
Page 56: ...2 2 14 Ver 0 10 This is a blank page ...
Page 88: ...3 3 32 Ver 0 10 ADDRESS SPACE 3 7 Notes on Address Space This is a blank page ...
Page 270: ...9 9 40 Ver 0 10 DMAC 9 4 Precautions about the DMAC This is a blank page ...
Page 614: ...12 12 64 Ver 0 10 This is a blank page SERIAL I O 12 9 Precautions on Using UART Mode ...
Page 756: ...17 17 10 Ver 0 10 RAM BACKUP MODE 17 4 Exiting RAM Backup Mode Wakeup This is a blank page ...
Page 762: ...18 18 6 Ver 0 10 OSCILLATION CIRCUIT 18 2 Clock Generator Circuit This is a blank page ...
Page 831: ...CHAPTER 22 CHAPTER 22 TYPICAL CHARACTERISTICS 22 1 A D Conversion Characteristics ...
Page 833: ...Appendix 1 1 Dimensional Outline Drawing APPENDIX 1 APPENDIX 1 MECHANICAL SPECIFICATIONS ...
Page 841: ...Appendix 3 1 Precautions about Noise APPENDIX 3 APPENDIX 3 PRECAUTIONS ABOUT NOISE ...